Derivatives of diaminodioxyarsenobenzene and process of making same.



"UN ED sT TEsf PATENT OFFICE.

onone KonNDtinPEn AND BAPTIST REN ER, or HocHs -oN-THE-MAIN, GERMANY,

AssreNoRs-To FABBWERKE vomvr. MEISTER LUCIUS & BnfiNINe, 0F nocnsT-oN-THE-MAIN, GERMANY, A CORPORATION or GERMANY.

DERIVATIVES OE DIAMINODIOXYARSENOBENZENE AND PROCESS MAKING SAME.

No Drawing.

Specification of Letters Patent.

Application filed April 20, 1912. serial No. 692,061.

Patented Feb. 18, 1913.

To all whom it may concern Be it known that we, GEORG K RNDiiRFER,

Ph.,D., chemist, and BAPTIST REUTER,Ph.D., chemist, citizens of theEmpire of Germany,

residing at Htichst-on-the-Main, Germany,

have invented certain new and useful Improvements 1nv Derivatlves ofDlaminodloxyarsenobenzene and Processes of Making Same, of which thefollowing is a specifica tion.

We have made the observation that byadding a solution offormaldehydesulfoxylate of the formula: CH,O.NaHSO .2H,O to solutions ofdiaminodioxyarsenobenzene,

precipitates are produced which are readily,

soluble in alkalis. In fact for completely dissolving the precipitatesthere is only required so small an excess of alkali that the solutionscan be regarded as being practically neutral. Such solutions retain theentire threapeutical efliciency of the pure di-'aminodioxyarsenobenzene, and owing to their neutral solubility theypresent in their therapeutical application considerable ad-. vantagesover the solutions from the d1hy-- drochlorid and the phenolate ofdiaminodioxyarsenobenzene. formaldehydesulfoxylate required forobtaining clear solutions may be varied withf;

in wide limits.

If a solution of diaminodioxyarsenobenzene prepared in the aboveindlcated man- ,ner is precipitated by means of hydrochloric acid,precipitates result which possess the property of an acid. They readilydissolve in alkalis and ammonia, the solutions thus obtained showing aneutral reaction if an' excess of alkali-is avoided. The composlt on ofthese acids varies, dependent on whether the sulfoxylate has reactedupon the di aminodioxyarsenobenzene at ordinary temperatures or at 60-70 C. In the former case an acid is produced comprising only one acidgroup containing sulfur; in the latter case an acid comprising two suchgroups. The general formula of the new compounds is as follows:

i I As-C H 6 a mix wherein 'X and Y stand for the resi due known asmethylene-sulfinic acid AS- Cam The quantity of the (-CH SO H), and X?may be replaced by hydrogen. These acids form bright yellOWlSh powders,difiicultly soluble in water and insoluble in alcohol, ether, acetone:and benzene. The corresponding alkali salts are obtained by dissolvingthese acids in the calculated quantity of caustic soda or potassium lye,aqueous ammonia or solutions,

is added, whereby a clear yellow solution is powders, readily solu-After one hour 80 i obtained which can be further diluted as desiredvandwhich remains clear when kept.

Example II: 25 grams of dihydrochlorid of diamlnodioxyarsenobenzene aredissolved in 250 grams of water, and there are then added, withstirring, a solution of 25 grams of formaldehydesulfoxylate in 250 gramsof water and after one hour ccms. of a 10% solution of sodium carbonate.To thevclear solution thus obtained are added 100 ccms. of hydrochloricacid of 12% strength. The precipitated acid is filtered off, washed anddried in 'vacuo; it comprises only one acid group containing sulfun Theformula of this new compound is:

I As-C H /o NHcmsonEl Example III ,For transforming the acid obtainedunder Example II into its sodium salt, 20 grams of the acid aresuspended in 70-80 grams of water, this suspension is dissolved byadding 20 ccms. of twice normal ,caustic soda lye, and the resultingsolution is poured in a thin stream into 1000 ccms. of

alcohol. The precipitate is filtered oif, washed with alcohol and driedin vacuo. The salt contains only one atom of sodium.

- Example IV: There is added to a finelydivided aqueous suspension of 21grams of the base of diaminodioxyarsenobenzene, a solution of 25 gramsof formaldehydesulfoxylate in 60 grams of water, and this mixture isgently'heated on the water-bath until it is completely dissolved. Thesolution is precipitated by 25 ccms. of concentrated hydrochloric acid,and the precipitated acid is further treated as indicated in Examples IIand III. The acid thus obtained contains two acid groups containingsulfur and its sodium salt two atoms of sodium.

Example V: 50 parts by weight of hydrochlorid ofdiaminodioxyarsenobenzene are dissolved in 200 parts of glycol and tothis solution is added another solution of 31 parts offormaldehydesulfox-ylate in 50 parts of water. After stirring for 5minutes, a solution of sodium carbonate is added until the solutionshows a neutral react-ion.

Thus results a solution of diaminodioxyar- I 'senobenzene of neutralreaction and ready for use, which can be diluted with water in anydesired proportion without the solution becoming turbid. If thissolution is run into large quantities of ethyl alcohol or a mixture ofethyl alcohol and ether, or acetone, a yellowish precipitate forms,which is also readily soluble in water with neutral reaction. In theplace of the glycol, in this example, other alcohols may be usedassolvents, for instance methyl alcohol, ethyl alcohol, glycerin or thelike.

Having now described our invention, what we claim'is:

; 1. The process of manufacturing new derivatives ofdiaminodioxyarsenobenzene,

which consists in reacting on diaminodioxarsenobenzene wlthformaldehydesulfoxylate.

2. As new products, the derivatives of d1aminodioxyarsenobenzene theradicals of which have the general formula:

AS-C5H3/ nnomsom said derivatives being yellowish powders, diflicultlysoluble in water, insoluble in alcohol, ether and acetone, dissolving inalkalis with formation of salts, these alkali-salts being yellowishpowders readily soluble in water.

3. As a new product, the derivative of the diaminodioxyarsenobenzenehaving the formula:

AS-CGH:

being a yellowish powder, difficultly soluble in water, insoluble inalcohol, ether and acetone and dissolving in alkalis with formation of asalt constituting, in the form of the sodium salt obtained with anequivalent of caustic soda, a yellowish powder readily soluble in waterwith neutral reaction.

In testimony whereof, we afiix our signatures in presence of twowitnesses.

GEORG KORNDClRFER. BAPTIST REUTER.

Witnesses:

JEAN GRUND, CARL GRUND.

